1. Field of the Invention
The present invention relates to surgical incision instruments such as scalpels. In particular this invention relates to scalpels that incorporate a laser.
2. Invention Disclosure Statement
Scalpels are an important basic tool used in surgical operations. However scalpels create an undesired flow of blood from the cut tissue area. Means to reduce blood flow and cauterize tissue are advantageous to the patient""s health as well as to provide the surgeon with an unobstructed view of the incised tissue. The most common method applied to reduce blood flow is heat-induced coagulation following a sharp edge scalpel incision. In addition to typical sharp edge mechanical scalpels, laser and ultrasonic scalpels are also available to make incisions. Prior art patents propose several ways to induce coagulation in conjunction with cutting. Laser and ultrasonic methods are an improvement over standard blade scalpels, but still these methods have only limited coagulating abilities. The use of an optical fiber to cauterize an area is problematic because optical fibers are difficult to drag through tissue and the hand-pieces that incorporate optical fibers are often unwieldy.
U.S. Pat. No. 5,366,456 describes a coagulating scalpel that uses a laser to cut through tissue. The described device is held above the area to be incises and does not contact the treatment area. This device uses the laser energy to cut as well as cauterize the tissue. The drawback to this device however, is that surgeons are generally accustomed and familiar with the tactile feedback that a standard blade scalpel provides.
U.S. Pat. No. 5,324,299 describes an ultrasonic scalpel. This type of blade generally vibrates at a rate of around 55,000 times per second. This vibration generates ultrasound waves that change the nature of the proteins in the tissue. This device in practice however, has only limited coagulating ability.
U.S. Pat. No. 4,627,435 describes a diamond knife coupled to a laser source. The radiation energy is used to heat the blade which cauterizes the tissue. This requires that the blade be heated to temperatures between 300-500xc2x0 C. This device is limited, because the entire blade and incision area is heated. This heating could cause undesired damage to tissue. Furthermore, using this device, it is not possible to cauterize only a specific area.
U.S. Pat. No. 5,571,098 describes a laser surgical device. This device is comprised of a mechanical cutting instrument such as a sharp edge scalpel, and an optical fiber attached to the handle area. Radiation is directed from the distal end of the handle to the incision area. The optical fiber allows radiation to be applied to tissue before the incision is made and therefore cauterize the tissue to be incised. A drawback to this invention is that the externally connected fiber can interfere with the use of the scalpel and make it difficult to control the incision area.
The present invention gives the benefits of a laser incision, while still providing the operator with tactile feedback. The present invention is also easier to use since the optical fiber is incorporated into the handle of the device. The problems with the prior art are overcome in these ways by the present invention.
It is an object of the present invention to provide a scalpel that can cut as well as cauterize tissue.
It is another object of the present invention to provide a laser scalpel that is easy to use and provides the operator with tactile feedback.
It is yet another object of the present invention to provide a scalpel that introduces minimum trauma.
Briefly stated the present invention provides a device that simultaneously incises an area and cauterizes the desired tissue. The device incorporates laser energy by some means into a mechanical scalpel so that the incised area is cauterized as well. For example, a laser source is coupled by some means to an optically transparent blade such as a diamond knife or quartz glass knife. The diamond knife is appropriately coated so that radiation only exits at desired areas. In another example, optical fibers are embedded into a sharp edge blade scalpel with means to couple to a suitable radiation source.
The above, and other objects, features and advantages of the present invention will become apparent from the following description read in conjunction with the accompanying drawings.